The nature of every viscosity liquid varies from solid-laden sludge and heavy fuel oil to paste-like food products and adhesives. Because of this, over the past 12 years, manufacturers have been making viscous fluid pumps, which include a wide range of pumping technologies so as to meet various application requirements.
Certain pumps, like centrifugal, struggle a lot with thicker or viscous fluids because of frictional loss in the pump, making flow rates decline rapidly. However, high viscosity pumps usually excel in such conditions.
Determining the Viscosity
Testing devices called viscometers are used to test or determine the viscosity of a liquid. These tests are carried through a range of temperatures and shear rates with results plotted in a graphical form.
Given flow rates through a specific pipe determines the rate of velocity. Determining the shear rate and temperature for the operating condition will help you dictate the viscosity of that condition.
Features of Viscous Liquids
No matter the application, the key goal is to maintain the flow efficiency of liquids through the continuous and consistent movement of products. This is a great challenge when it comes to thick fluids since their efficiency decreases as their viscosity increases.
In addition, viscosity changes and patterns might occur when pumping through your systems, affecting the flow as well as other measurements, such as line loss and pressure. Viscous liquids behave in different ways. Some of these fluids include:
- Thixotropic liquid
- Dilatant liquid
- Non-Newtonian liquid
- Newtonian fluid
Better Options for Thicker Liquids
When choosing a system for viscous liquids, you can consider trash pumps. As their viscosity increases, the flow rates do too. This is because a higher viscosity liquid fills the clearances of pumps, resulting in higher volumetric efficiency.
Plus, as the viscosity increases, you will see a better efficiency rate. Because centrifugal pumps work at motor speed, efficiency usually goes down as the viscosity increases as a result of more frictional loss in the pump. A trash pump will basically not experience such a decrease in efficiency.
How to Choose the Best Pumps for Viscous Liquids
Firstly, you need to know the viscosity of the materials you want to pump. A perfect way to achieve this is to use a viscometer. Though this device only measures viscosity under one flow condition. You can use a rheometer instead for a fluid with viscosity, which may differ depending on flow. Consider a rheometer a special kind of viscometer.
Typically, these devices operate by keeping the device running fluid and keeping the device stationary or through stationary liquids. The drag that a relative motion of fluids causes is the general measure of viscosity.
Determining the thickness of the fluid you want to pump will help you to choose the right pump. To also make the process easy, you might also want to look at the following factors:
- Presence of discharge tanks
- Length of a discharge circuit
- Discharge head
- Suction head
Final Thoughts!
Not every pump is created the same. Although pumps are found everywhere, from chemical vats and fuel depots to swimming pools, each application might have its own share of challenges. Therefore, if you’re dealing with thicker liquids, it’s advisable to invest in the best pump suitable for viscous fluids.
